Drier



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Oct. 18, 1927.

F. c; CHAPMAN DRIER Filed .Anril 7.- 1926 3 Sheets-Sheet 2 INVENTOR 1 7C Char Jinan Oct. 18, 1927s F c CHAPMAN DRIER Filed April 2 3 Shets-Sheet 3 zmN Patented Oct. 18; 1927.

UNITED STATES FRANK C. CHAPMAN, OF MODESTO, CALIFORNIA.

DRIER.

Application filed April 7,

This invention relates to the art of drying generally and particularly to driers of the house and kiln type, the present application being directed to certain improvements and additions to the structure shown in my issued Patent No. 1,404,369 dated J anuary 24th, 1922. v In a drier of the type under consideration the heated air is admitted to the center of the tunnel and flows both ways -over the material to be dried. In the interest of efficienc'y and economy a portion of the moisture laden air is allowed to escape to the atmosphere and the balance returned to the source and there mixed with fresh air in suflicient volume to replace that allowed to escape. One of the principal objects of the present invention is to provide a means whereby this control of the air is carried on in a most simple, inexpensive yet effective manner with a special provision for a most thorough and controlled mixing of the returned and new air.

In the type of drier referred to the cars or trucks carrying the material to be dried are moved along a track in a tunnel kiln and the drying air, as has been already indicated, is moved into the tunnel centrally thereof and then passed to the ends of the tunnel. The cars are moved successively; through the tunnel, i. e. as one is removed at one end another is entered at the opposite end, all cars within the tunnel moving toward the outlet end accordingly.

Until our present improved and herein described method of handling the cars within the tunnel, as the cars were moved therethrough, each car would for a period of time stand immediately adjacent the inlet of the incoming hot air which resulted in the material being improperly dried at the point where the direct blast-of the hot air hit it.

It is therefore another and most important aim of the present invention to provide a method andmeans whereby, with the advancement of the cars through the tunnel each car will skip the space immediately adjacent the air inlet. This will result in leaving this space freely open which will prevent the improper drying of the fruit as above related, and will also allow a more even distribution of the heated air against the two lines of trucks standing on opposite sides of such open space.

1926. Serial in. 100,245.

method and means of skipping the car s across the area adjacent the hot air inlet.

Fig. 3 is a vertical section through a port1on of a modified form of drier housing.

Fig. 4 1s a fragmentary view of the rear end of the furnace housing showing the door controlled opening from the atmosphere into the furnace mixing room.

Referring now more particularly to the characters of reference 0n the drawings the numeral 1 designates the drying housing which in my invention consists of an elongated tunnel having a central track 2 on which the cars or trucks 3, carrying the materlal to be dried, are successively advanced through the tunnel. I

Directly at each end of the tunnel 1 are two doors 4. and 5 respectively, preferably opening by sliding ,them vertically.

In one side wall of the tunnel at each end thereof are doors 6 and 7 respectively, preferably opened by sliding them lengthwise of the tunnel wall. These doors 6 and 7 open lnto a return flue orconduit 8 leading to a relatively large air mixing room 9 open for its entire front area to the said flue 8.

A hot air furnace 10 of any desired type i is arranged to discharge hot air directly into the room 9. A door controlled 0 ening 11 is arranged preferably above the irnace 10 to admit atmospheric air into the mixing room 9 as desired. The size of the opening 11 is determined by positioning the sliding door 11 at such point deemed advisable for x the admission of atmospheric air into the mixing room.

A large fan blower 1 2, suitably driven by motor, pulley and belt assembly 13 is located to one side of the large air mixing room 9 and the inlet of the fan is in communication with such room 9 through the opening 14.

The outlet of the fan 12 communicates with a conduit or flue opening to discharge approximately centrally into the tunnel 1 preferably through the bottom floor thereof as shown in the drawings.

Centrally of the track 2 and crossing over the flue 15 is a channel shaped guide 16.

Slidable in this guide is a flat plate 17. Pivoted on this plate as at 18 is a spring pressed pawl or dog 19. The pressure of the spring normally holds the pawl 19 up above the plane of the track 2 so that when advancedin the direction of the movement of the cars 3 it will engage and push one of the cars along and when moved in the returndirection the engagement of the cars therewith will press it down against its spring so it will pull along under the cars, all for a purpose as will presently appear. A cable 20, connects with opposite ends of the bar 17 and-extends through the tunnels and out the doors 4 and 5 and can be op-- erated by hand or power at will. A grapple 21 of any desired form is provided on the cable 20 at the inlet end of the tunnel so that it may be engaged with the rearmost car so that with the'draw on the cable all of the cars will be advanced through the tunnel in the manner described.

The movement of the bar 17 is the length of one car plus the width of the flue 15. Thus when the cable is pulled back it is pulled this length. This brings the pawl 19 to a point back of the car immediately adjacent the edge of the flue 15 and its spring lifts it into' contact with the back edge of such car. The forward pull on the cable then first advances this car across the flue opening 15, leaving a like space between it and the next car to the rear of it. By this time the grapple 21 has-moved up to the- I engaging point with the car 3 waiting outside of the entrance of the. tunnel to be advanced into the tunnel. Such grapple is then engaged with the said outside car. Then with the continued draw on the cable the outside car is drawn into the tunnel and the whole line of cars moved up to discharge one car out of the exit of the tunnel. This brings the string of cars on the entrance side of the tunnel up to the edge of I flue 15 on that side and moves the string on the exit side to clear said flue 15 on that side. This leaves thespace in the tunnel adjacentsuch flue 15 perfectly free and open as shown in Fig. 2 with the two strings of cars spaced on each side thereof. This avoids the objections noted in the preamble to this specification. With this free space available I can place a deflecting plate 22 in the flue 15 immediately adjacent its opening into the tunnel and this will cause the incoming air to distribute substantially equally over the ends of the two lines of cars which will cause it to move evenly through the length of the cars, thus tending to uniformity in the drying of the material. In using the dehydrator the tunnel is filled with the trucks carrying the material to be dried, such trucks being positioned as described. U

The end doors 4 and 5 are then closed and the side doors 6 and 7 opened. The heated air from the furnace 10 is then drawn from the mixing room 9 into the fan 12 through the opening 14 and discharged by the fan into the tunnel through the flue 15. The forced draft of the fan in one direction plus the suction thereof through the mixing'room 9, flue 8 and door openings 6 and 7 causes the heated air to circulate freely through the tunnel and over the material to be dried. As the heated air passes over the material to be dried it naturally gathers humidity therefrom and as it is desired to release some of this humidity as the drying action proceeds this is accomplished by raising the doors 4 and 5 a slight distance which will allow a portion of-the air to escape to the atmosphere, an equal amount being replaced in the mixing room 9 through the controlled openmg 11.

The amount of air passing through each end of the tunnel may be easily controlled and varied according to required conditions, by controlling the open and closed positions of'the several doors and the size of the open-- ing 11. Thus if certain materials require an escape of a considerable amount of moist air at the entrance end to insure best results, then the .door 4 would be openedaccordmgly and the door 6 could be partly closed accortt ing to conditions required; and likewise the exit end can be similarly controlled.

The relatively large mixing room 9 insures a perfect mixing and uniform heating of the air from the tunnel and the atmospheric air inlet as the inflowing' air currents have a large area in which to flow together and mix with a of the heat and moistur In the use of the drier for certain classes of material it sometimes happens that it is essential that the incoming material be first subjected to a zone of high humidity and relatively low temperature, this being especially true of lumber. To this end I have introduced secondary doors 6 and 7 a in the side wall of the tunnel intermediate the air inlet 15 and the doors 6 and 7 respectively. Thus when it is desired to establish a dead zone of hot air of high humidity for themcoming material, the doors 4'and 6 may be closed and the door 6 opened. Then the cars in the zone between the intake door 4 and the secondary door 6 will stand for a period of time in hot but dead air since the air currents from the opening 15 will be passing out through the door 6. Thus for a period of time the material in such zone perfect distribution spect to those in the others.

will be heated through and thoroughly sweated without any direct drying aetion. As it then passes on into the drying air cur rents it will be thoroughlyand efliciently and uniformly dried without case hardening or cracking since the pores will have been all opened and prepared for the drying process by the thorough heating and sweating received in the dead air zone.

At the opposite end of the tunnel gradual cooling of the material may be had by closing the door 7 and opening the door 7 a and slightly opening the door 5. The forced air currents passing through the tunnel and out the door 7 a will draw a small amount of cool air through the opening in thedoor 5 over the material, thus gradually cooling it.

The structure of the tunnel shown in the primary views ,.of the drawing is that used where the containers for the material to be dried, or the material itself, is placed horizontally in the tunnel so that the air currents pass horizontally therethrough. Fig. 3 shows a modified form of tunnel construction for use when the material to be dried, such as lumber, plaster wall board or the like must be placed vertically edgewise in the tunnel and in order for the air currents to pass therethrough they must likewise be moved vertically through the material. To this end air spaces 23 are provided either at the top or bottom of the tunnel. In these air spaces are arranged deflectors 24, those in one space being disposed alternately with re- These deflectors extend clear across the space to a position immediately adjacent the material to be dried. Thus the air currents leaving the air inlet 15 will move into the spaces 23 and be diverted by the alternately disposed deflectors 24 into an alternate back and forth movement through the vertically disposed material, as shown by the arrows in Fig. 3.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from 1 such detail may be resorted to as do not form f as definediby the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is: 1. A drier comprising a tunnel having a hot air inlet, means for advancing material to be dried through the tunnel and past the air inlet and maintaining the space in the tunnel immediately adjacent the. air inlet freely open between the advancing material. 2. A drier comprising a tunnel having a hot air inlet, means for advancing material to be dried through the tunnel and causing the material in its advance to skip across the air inlet to continuously leave a freely open space in the tunnel adjacent such air inlet.

3.:A drier comprising atunnel having to advance the material carriers, and an in termediate element carried by the cable to engage and carry each material carrier across the area adjacent the inlet.

4. A drier comprising a tunnel having a hot air inlet, a means for maintaining a line-of material carriers within the tunnel and keeping-"said line split adjacent and across the mjr inlet area so as to leave that area continuouslyand freely open'to the air entering through the air inlet.

5. A drier comprising a tunnel having a hot air inlet, means for advancing a material carrier to a point at one side of the inlet and then skipping the, carrier across the area adjacent the inlet whereby to leave such area at all times freely open to the incoming air.

v6. The combination with a drier of the tunnel type having a hot air inlet, of a means to maintain a line of material carriers on each side of the inlet while leaving the intervening space freely open to the incoming a1r.

7. A drier comprising a tunnel, a controllable door opening at each end, a return flue adjacent the tunnel for the length thereof, a controllable door opening from each end of the tunnel into the return flue, a mixing room to which the return flue leads, and a means for driving the air from the mixing room into the tunnel.

8. A drier comprising a tunnel, a controllable door opening at each end, a return'v flue adjacent the tunnel for the length thereof, a controllable door opening from each end of the tunnel into the return flue, a mixing room to which the return flue leads, a

means for driving the air from the mixing room into the tunnel, and means for admitting atmospheric air to themixing room.

9. A drier comprising'a tunnel, a controllable door opening ateach end, a return'flue adjacent the tunnel for the length thereof, a controllable door opening from each end of the tunnel into the return flue, a mixing room to which the return flue leads, a means for driving the air from the mixing room into the tunnel, means for admitting atmospheric air to the mixing room, and a hot air furnace discharging into the mixing room." c

10. A drier including a tunnel anda return flue from each end of the tunnel, a relatively large mixing room freely open at one side to the return flue, a controlled opening to admit atmospheric airto the mixing room, a hot air furnace discharging into themixing room, and means for passing air from'the mixing room under pressure into the tunnel.

11. A drier including .a tunnel and a re: turn flue from each end of the tunnel, a relatively large mixing room freely open at one side to the return flue, a controlled opening to admit atmospheric. air to the mixing room, a hot air furnace discharging into the mixing room, means .for passing air from the mixing room under pressure into the tunnel, and means for allowing egress of air from the ends of the tunnel.

the

I 12 A drier comprising a tunnel havinga hot air inlet, means for maintaining a line i of material carriers on each side' of the inlet, leaving the intervening space clear, and a deflector'in the inlet to distribute the incoming air substantially evenly over the full end of each line of material carriers.

13. A drier including a tunnel provided with a door in its end, and anair inlet, a return flue adjacent the tunnel and in communication with the air inlet, the tunnel being provided with a side door adjacent the end door and another door intermediate the side door and the air inlet. In testimony whereof I aflix my signature.

FRANK C. CHAPMAN. 

